A vehicle having an engine is known. Many engines are cooled by using coolant. Coolant is circulated by a water pump. For example, an electric water pump is used. When the temperature of coolant is higher than a threshold value, coolant is circulated by an electric water pump to cool an engine. On the other hand, when the temperature of coolant is lower than a threshold value, the electric water pump is stopped to facilitate engine warm-up.
The temperature of coolant is leveraged for controlling an electric water pump and also for performing various controls for an engine. However, in a state where the electric water pump is stopped, the difference between the temperature at a location where a coolant temperature sensor is provided and the temperature at a location remote from the coolant temperature sensor may become large. For example, there may be a case where the temperature at a location away from a coolant temperature sensor is low even though the temperature detected by the coolant temperature sensor is high. In such a case, the overall temperature (for example, the average temperature) of coolant can be said to be low. To minimize such a difference, it is preferable that an electric water pump is driven for a predetermined period of time, as disclosed in the fourth paragraph of Japanese Patent Laying-Open No. 2008-169748.